How does being a Starbucks customer work?

Can any of my American Friends help with this query?

How do you get served in a Starbucks in the USA if you're going to drink the coffee on the premises? I need to know for a scene in the Epilogue of 'The King of Elfland's Daughter' and I haven't been able to find out on the Starbucks site or by Googling. Do you order at the counter, then sit down, and is your order brought to you? Do you order at the counter, wait, and then take your order to a table? Do you sit down and a waitress comes to you (I'm pretty sure it's not this one, but not absolutely certain)? I've seen posts on Cheezburger.com implying that they write your name on your cup but I have no idea how that would work - especially as the menu on their website shows proper cups rather than paper ones. I've only ever been to a Starbucks once, and that was in York about five years ago, so I remember little about it and it probably wouldn't be relevant anyway.

If there are regional differences in the service this would be, specifically, in Washington DC.